Bradford White URG1PV40S, URG1PV50S, URG2PV40T, URG2PV50T, URG2PV50H Service manual

UPV Series

Through-The-Wall Gas Water Heaters

SERVICE

MANUAL

Troubleshooting Guide

and Instructions for Service

(To be performed ONLY by

qualified service providers)

Models Covered

by This Manual:

URG1PV40S*N
URG1PV50S*N
URG2PV40T*N
URG2PV50T*N
URG2PV50H*N
ULG2PV50H56*N
(*) Denotes Warranty Years

Manual 238-51548-00B 8/18

Save this manual for future reference

The Bradford White

UPV Series

Through-The-Wall Gas Water Heaters

Table of Contents

Page PV Service Procedure

Introduction.................................................................................................................................4 ---

How to Use This Manual ..........................................................................................................5 ---

Tools Required for Service........................................................................................................5 ---

Specifications..............................................................................................................................6 ---

Control Timings.........................................................................................................................9 ---

Sequence of Operation ..............................................................................................................10 ---

Troubleshooting.........................................................................................................................14 ---

Burner Inspection, Cleaning & Replacement .......................................................................... 16 I

Pilot Testing, Cleaning & Replacement ................................................................................... 18 II

Pressure Switch Testing & Replacement ................................................................................. 19 III

Blower Testing & Replacement ...............................................................................................21 IV

Blower TemperatureSwitch Testing & Replacement ............................................................23 V

Gas Control Testing & Replacement........................................................................................25 VI

Flammable Vapor Device Testing and Replacement..............................................................28 VII

Safety Circuit Voltage Trace.....................................................................................................29 VIII

115 VAC Circuit Trace .............................................................................................................30 IX

Diptube Inspection & Replacement..........................................................................................31 X

Anode Inspection & Replacement............................................................................................32 XI

Flue Baffle Inspection & Replacement ....................................................................................33 XII

Inner Door Removal, Inspection & Replacement................................................................... 34 XIII

Resettable Thermal Switch, Inspection & Replacement.........................................................37

®

ScreenLok

Glossary of Terms......................................................................................................................40

Parts List .....................................................................................................................................41 ---

2

2

Flame Arrestor Cleaning ..................................................................................... 39

XIV

---

---

UPV Series

WARNING: If the information in these

instructions is not followed exactly, a fire or
explosion may result causing property damage,
personal injury, or death.

WHAT TO DO IF YOU SMELL GAS!

x

Do not try to light any appliance.

Do not touch any electrical switch; do not use any

x

phone in your building.

Immediately call your gas supplier from a neighbor's phone.

x

Follow the gas supplier's instructions.

If you cannot reach your gas supplier, call the fire

x

department.
Installation and service must be performed by a qualified
installer, service agency or the gas supplier.

DANGER

Do not store or use gasoline or other flammable,
combustible, or corrosive vapors and liquids in
the vicinity of this or any other appliance.

IMPORTANT

Before proceeding, please inspect the

water heater and its components for

possible damage. DO NOT install any

water heater with damaged

components. If damage is evident
then please contact the supplier where
the water heater was purchased or the

manufacturer listed on the rating plate

for replacement parts.

WARNING

Water heaters are heat producing appliances. To avoid damage

or injury, do not store materials against the water heater or vent-

air intake system. Use proper care to avoid unnecessary contact

(especially by children) with the water heater and vent-air intake

components. UNDER NO CIRCUMSTANCES MUST

FLAMMABLE MATERIALS, SUCH AS GASOLINE OR PAINT

THINNER BE USED OR STORED IN THE VICINITY OF THIS

WATER HEATER, VENT-AIR INTAKE SYSTEM OR IN ANY

LOCATION FROM WHICH FUMES COULD REACH THE

WATER HEATER OR VENT-AIR INTAKE SYSTEM

CAUTION

If sweat fittings are to be used DO NOT apply heat to the nipples

on top of the water heater. Sweat the tubing to the adapter

before fitting the adapter to the water connections. It is

imperative that heat is not applied to the nipples containing a

plastic liner.

WARNING

Hydrogen gas can be produced in an operating water heater that

has not had water drawn from the tank for a long period of time

(generally two weeks or more). Hydrogen gas is extremely

flammable. To prevent the possibility of injury under these

conditions, we recommend the hot water faucet to be open for

several minutes at the kitchen sink before you use any electrical

appliance which is connected to the hot water system. If
hydrogen is present, there will be an unusual sound such as air
escaping through the pipes as hot water begins to flow. Do not

smoke or have open flame near the faucet at the time it is open.

WARNING

DO NOT ATTEMPT TO LIGHT ANY GAS APPLIANCE IF YOU ARE
NOT CERTAIN OF THE FOLLOWING:

x

Liquefied petroleum gases/propane gas and natural gas
have an odorant added by the gas supplier that aids in the
detection of the gas.

x

Most people recognize this odor as a “sulfur” or “rotten egg”
smell.

x

Other conditions, such as “odorant fade” can cause the
odorant to diminish in intensity, or “fade”, and not be as
readily detectable.

x

If you have a diminished sense of smell, or are in any way
unsure of the presence of gas, immediately contact your gas
supplier from a neighbor’s telephone.

Gas detectors are available. Contact your gas supplier, or plumbing
professional, for more information.

WARNING

FAILURE TO INSTALL AND MAINTAIN A NEW, LISTED ¾” X ¾”

TEMPERATURE AND PRESSURE RELIEF VALVE WILL RELEASE

THE MANUFACTURER FROM ANY CLAIM THAT MIGHT RESULT

FROM EXCESSIVE TEMPERATURE AND PRESSURES.

CAUTION

Turn off or disconnect the electrical power supply to the water heater
before servicing. Label all wires prior to disconnection when servicing
controls. Wiring errors can cause improper and dangerous operation.
Verify proper operation after servicing.

3

3

The Bradford White

The new Bradford White URG1PV & URG2PV water heaters are designed to provide reliable performance
with enhanced standard features. New design features include reliable spark to pilot ignition system,
enhanced diagnostics, simplified servicing, significantly quieter operation, additional vent lengths, and
Bradford White Defender Safety System

Spark to Pilot Ignition System - employing the spark to pilot ignition system promotes reliable and consistent
pilot and main burner ignitions to provide hot water on demand.

Integrated Immersion Thermostat/Gas Control Valve with LED - was developed for ease of troubleshooting
by providing simple diagnostic codes to pinpoint an installation or component performance issue.

Powerful Blower - will eliminate problems with difficult venting situations.

Quieter and Cooler Blower Operation - blower noise is significantly reduced for both interior and exterior
environments. Cooler operation increases blower life by reducing bearing wear and noise.

Rugged Wiring Connections - receptacle type connections promote free wiring.

Increased Vent Lengths - increased venting performance is achieved while maintaining Energy Factor &
FHR (not applicable on all models) performance.

The URG1PV & URG2PV water heaters use a combustion system where flue gases are combined with
dilution air to reduce the flue gas temperature in the blower. The diluted flue gases are evacuated to the
exterior through low temperature vent materials. The gas control maintains water temperature, ignition
sequence and regulates gas flow. A safety circuit consisting of a pressure switch and blower temperature
switch verifies proper conditions exist for safe and reliable operation. If a situation outside of normal
operating parameters exists, the gas control diagnostic LED will flash a code to positively identify an
operational issue.

Introduction

®

(not available on all models).

This service manual is designed to facilitate problem diagnosis and enhance service efficiency. Please read
the service manual completely before attempting service on this new series of power vent models.

How the Safety System Works

During normal operation, most air for combustion is drawn into the water heater through the openings in the
jacket door. This air travels into the burner venturi, mixing with the gas jet. This air is then mixed with gas
inside the burner and drawn to the burner screen and is efficiently combusted producing Ultra Low NOx
emissions. Additional air is drawn through the openings in the jacket. This air travels down and around the
combustion chamber and enters through holes in the bottom of the corrosion-resistant combustion chamber.
The air then travels up through the oriented flame arrestor plate louvers, where they velocity of the air is
increased and its direction altered. The air then mixes in a normal manner with the combustion products
from the burner.

In the case where trace amounts of flammable vapors are present in the air flowing into the combustion
chamber and burner venturi, the vapors are harmlessly ignited by the burner/pilot flame. If flammable vapors
are in sufficient quantity to prevent normal combustion, the burner and pilot flames are designed to shut
down.

Should the flammable vapors continue to the burner, the flame arrestor plate and burner screen prevent the
flames from traveling backwards and igniting vapors outside of the combustion chamber. The gas control
utilizes a flammable vapor sensor to detect the presence of flammable vapors and shut down if the vapors
achieve a certain level.

4

4

UPV Series

How to Use This Manual

It is intended for this manual to be used by qualified service personnel for the primary purpose of
troubleshooting and repair of the Bradford White UPV Series water heaters. Understanding the sequence of
operation section of this manual will contribute greatly to troubleshooting the water heater.

The Honeywell WV4462A Electronic Gas Control will display status codes in the event of abnormal
operation. Status codes are listed in the troubleshooting chart beginning on page 14 of this service manual.
The troubleshooting chart will also indicate the probable cause for the status code and direct the service
professional to a service procedure to properly diagnose the abnormal operation.

In some difficult to diagnose conditions, it may be necessary to isolate the heater from the vent system to
determine the problem.

Contact the Bradford White technical support group immediately if diagnosis cannot be made using the
methods described in this service manual.

Tools Required for Service

Manometer:

Multi-Meter:

Electronic Probes:

Thermometer:

Water Pressure Gage:

Various Hand Tools:

A liquid “U” tube type or a digital (magnahelic) type can be used. This
device is used to measure gas and/or air pressure and vacuum.

A digital type is strongly recommended. This device is used to measure
electrical values. The meter you select must have the capability to
measure volts AC, volts DC, Amps, micro-amps and ohms.

In some cases, standard multi-meter probes will damage or simply not be
effective to obtain certain voltage and ohm readings. It will be necessary to
have special electronic “pin” type multi-meter probes. These probes are
available at most electronic wholesale outlets.

Used to measure water temperature. An accurate thermometer is
recommended.

Used to measure water supply pressure. Also used to determine tank
pressure by adapting to the drain valve of the heater.

Pipe wrench, channel locks, open end wrenches (3/8”, 7/16”, 1/2”), 12”
crescent wrench, allen wrench set, screw drivers (common & Phillip’s), 1/4”
nut driver, pliers (common & needle nose), socket set, side cutters, wire
cutters, wire strippers, wire crimpers, torpedo level, small shop vac, step
ladder, flashlight and 5 gallon pail.

5

5

UPV Series

Power Supply Dedicated 115 VAC, 60 Hz, 15A.
Gas Supply Pipe Minimum 1/2” NPT (schedule 40 black iron pipe recommended).
Approved Gas
Type
Gas Pressure 6.0” W.C. min. for Natural Gas, 14.0” W.C. maximum.
Venting System Power vent through the wall or vertical through the roof.
Approved Vent
Materials
Minimum
Clearance for
Servicing
Water Supply
Pressure
Gas Control
ECO Limit
Residential
Temperature Set
Point Range
Commercial

Temperature Set
Point Range

Natural Gas, unit must match gas type supplied.

PVC, CPVC or ABS.

18” from top, 24” from front, 4” sides and rear.

150 PSI maximum allowable working pressure. Check local codes for supply
pressure.

Residential 188°F (87°C), Commercial 199°F (93°C).

60°F (16°C) to 160°F (71°C) (approximate temperatures).

80°F (27°C) to 180°F (82°C) (approximate temperatures).

Blower
Temperature
Switch

Pressure Switch

Blower

Normally closed, opens @ 155°F (68°C), auto reset @ approximately 135°F (57°C).

URG1PV(40,50)S Models: Normally open, closes on vacuum increase @ -.75” W.C.;
Opens on vacuum decrease @ -.72” W.C.
RG2PV(40,50)T: Normally open, closes on vacuum increase @ -.80” W.C.;
Opens on vacuum decrease @ -.77” W.C.
URG2PV50H Models: Normally open, closes on vacuum increase @ -1.40” W.C.;
Opens on vacuum decrease @ -1.37” W.C.
115 VAC, 60 Hz, 3.1 amps, 3000 RPM.

6

6

UPV Series

Vent Tables

Venting Specifications for:

URG1PV40S, URG2PV40T
URG1PV50S, URG2PV50T

2" Diameter (5.1 cm) Vent Connector Lengths

Terminating

# of

Elbows

Maximum Straight

Length ft. (m)

Minimum Straight

Length ft. (m)

Through the Wall

Through the Wall

Through the Wall

Through the Wall

Through the Roof

Through the Roof

Through the Roof

Through the Roof
Through the Roof

3" Diameter (7.6 cm) Vent Connector Lengths

Terminating

Through the Wall

Through the Wall

Through the Wall

Through the Wall

Through the Wall

Through the Roof
Through the Roof

Through the Roof

Through the Roof

Through the Roof

1

2

3

4

0

1

2

3
4

# of

Elbows

1

2

3

4

5

0
1

2

3

4

45 (13.7) 2 (.6)

40 (12.2)

35 (10.7) 2 (.6)

30 (9.1) 2 (.6)

50 (15.2) 7 (2.1)

45 (13.7)

40 (12.2) 7 (2.1)

35 (10.7) 7 (2.1)

30 (9.2) 7 (2.1)

Maximum Straight

Length ft. (m)

115 (35) 10 (3.1)

110 (33.5)

105 (32.0) 10 (3.1)

100 (30.5) 10 (3.1)

95 (29.0) 10 (3.1)

120 (36.6) 15 (4.6)

115 (35)

110 (33.5)

105 (32.0) 15 (4.6)

100 (30.5) 15 (4.6)

Minimum Straight

Length ft. (m)

2 (.6)

7 (2.1)

10 (3.1)

15 (4.6)

15 (4.6)

7

7

UPV Series

Vent Tables

Venting Specifications for:

URG2PV50H
ULG2PV50H

3" Diameter (7.6 cm) Vent Connector Lengths

Terminating

# of

Elbows

Maximum Straight

Length ft. (m)

Minimum Straight

Length ft. (m)

Through the Wall

Through the Wall

Through the Wall

Through the Wall

Through the Roof
Through the Roof

Through the Roof

Through the Roof

4" Diameter (10.2 cm) Vent Connector Lengths

Terminating

Through the Wall

Through the Wall

Through the Wall

Through the Wall

Through the Wall

Through the Roof

Through the Roof

Through the Roof
Through the Roof

Through the Roof

1

2

3

4

0

1

2

3

# of

Elbows

1

2

3

4

5

0

1

2
3

4

55 (16.8) 2 (.6)

50 (15.2)

45 (13.7) 2 (.6)

40 (12.2) 2 (.6)

60 (18.3) 7 (2.1)
55 (16.8)

50 (15.2) 7 (2.1)

45 (13.7) 7 (2.1)

Maximum Straight

Length ft. (m)

175 (53.3) 10 (3.1)

170 (51.8) 10 (3.1)

165 (50.3) 10 (3.1)

160 (48.8) 10 (3.1)

155 (47.2) 10 (3.1)

180 (54.9) 15 (4.6)

175 (53.3) 15 (4.6)

170 (51.8) 15 (4.6)
165 (50.3) 15 (4.6)

160 (48.8) 15 (4.6)

Minimum Straight

Length ft. (m)

2 (.6)

7 (2.1)

8

8

UPV Series

Control Timings

Ignition State Timing

Pre-purge
Trial for Ignition 90 Seconds

Flame Stabilization Period
Inter-purge

Flame Failure Response Time

Post-purge 15 Seconds
PS Fault Delay (failed open/close) Retry after 2 minutes
Soft Lockout Retry after 5 minutes
ECO Limit Lockout Indefinite (see page 26)
Verify Resistive Delay Retry after 2 minutes (repeats 5 times)
Flammable Vapor Sensor/Simulated Resistive Load
Lockout

Hardware Status Lockout

15 Seconds

3 Seconds
15 Seconds

1.5 Seconds (2 second maximum; 1 second
minimum)

Indefinite (cycle power to restart)

Indefinite (self clears if fault clears for at least 15
seconds)

9

9

UPV Series

Power Up Sequence

1. Start Up.

Upon power up, the control runs a safe-start check with a typical start-up delay of 5
seconds.

2.

Flammable Vapor.
To assure no outputs are energized if the “Flammable Vapor Sensor” is out of
range, the control will test the “Flammable Vapor Sensor” or “Simulated Resistive
Device” for proper operating range. If the “Flammable Vapor Sensor” or “Simulative
Resistive Device” is out of range, the control LED immediately flashes 7 times with
3 second pause.

Normal Heating Sequence

1.

Thermostat calls for heat.
Prior to energizing blower, gas control checks safety circuit to ensure the circuit is
open. Normal switch positions in the safety circuit are as follows:

a) Pressure switch normally open.
b) Blower temperature switch normally closed.

If the safety circuit is closed, the control waits 4 seconds, gas control LED
flashes 2 times with 3 second pause. Gas control waits 2 minutes then,
blower runs for 30 seconds. This cycle repeats until safety circuit opens.

2.

Blower energizes.
Pressure switch proves blower/vent system operation.

3.

If the pressure switch does not close within 30 seconds, the control LED flashes 3
times with 3 second pause. The blower runs for 30 seconds every 2 minutes trying
to get the pressure switch or blower temperature switch to close. This cycle repeats
as long as there is a call for heat.

4.

Blower pre-purge period (2 seconds).
Trial for pilot ignition (90 seconds).

5.

a.

The gas control lights the pilot by activating spark igniter and gas flow to pilot
burner.

b.

If flame is not sensed within 90 seconds, igniter and gas flow are
deactivated, blower will post purge and control LED flashes 6 times with 3
second pause.

6.

Main burner ignition.
After pilot flame is sensed, gas control activates main valve for main burner ignition.
The gas control will ignore flame and pressure switch signals for 3 seconds allowing
for main burner to stabilize.

10

10

UPV Series

Normal Heating Sequence (cont.)

7. Steady state operation.

During steady state operation, the control monitors:

Thermostat temperature sensor-when set point temperature is satisfied, gas
valve is shut down and blower will post purge for 15 seconds. Control LED flashes
a short flash once every 4 seconds (idle) status code.

Pressure switch / blower temperature switch-if either switch opens, pilot valve
and main valve shut down. The blower continues to run for 30 seconds attempting
to close the circuit. The control LED flashes 3 times with 3 second pause.

Flame sensor-if flame is lost, pilot & main valves are shut down, blower runs for 15
seconds. Control attempts to re-light pilot 4 times. If unsuccessful, blower is shut
down and control proceeds to 5 minute lockout. Control re-attempts to light pilot
starting at normal heating sequence #2.

8.

Thermostat satisfies. (Control LED flashing once every 4 seconds).
Burner off.

9.

10. Blower post purges (15 seconds).

Abnormal Operation

1.

Flammable Vapor Sensor or Simulated Resistive Device Fault:

a.

If the resistance is greater than 70,000 Ohms-the gas control immediately
turns off all outputs. Control waits and monitors resistance for 30 seconds.
If the resistance is greater than 65,000 ohms after 30 seconds, the gas
control proceeds to verify resistive delay for 2 minutes and flashes 7 times
then once with a three second pause. This process is repeated 5 times until
the control either returns to normal operation or proceeds to flammable vapor
lockout.

b.

If the resistance is below 3000 Ohms-The gas control immediately turns
off all outputs and proceeds to flash 8 times then once with three second
pause. The status self clears if the resistance returns to normal range for at
least 15 seconds.

2. Temperature Sensor Fault:
a.

Temperature sensor detected open circuit–The gas control immediately
turns off all outputs and proceeds to flash 8 times then, 3 times with 3
second pause. The status self clears if the fault clears for at least 15
seconds.

b.

Thermal well sensor not reading the same temperature within ±5.5°F –
The gas control immediately turns off all outputs and proceeds to flash 8

11

11

UPV Series

Abnormal Operation (cont.)

times, then 3 times twice with 3 second pause. The status self clears if the
fault clears for at least 15 seconds.

c. Water temperature in excess of ECO (energy cut out) limit -The gas

control immediately turns off pilot & main valves and proceeds to flash 4
times with 3 second pause. Blower continues to run until gas control is reset.
To reset control, rotate knob of temperature control to the minimum setting
for at least 6 seconds before returning to desired temperature setting.

3. Pressure Switch/Blower Temperature Fault:
a.

Pressure switch closed at start of call for heat-the gas control waits 4
seconds then, proceeds to flash 2 times with 3 second pause. The control
waits 2 minutes and then turns on blower for 30 seconds. The blower turns
off after 30 seconds and the control waits for pressure switch to open. Any
time the pressure switch opens, the blower turns on (or stays on) and the
control proceeds to wait for pressure switch to close.

b.

Pressure switch or blower temperature switch failed to close-the gas
control runs the blower for 30 seconds waiting for the pressure switch and/or
blower temperature switch to close. If either switch does not close in 30
seconds, the blower turns off and the control flashes 3 times with 3 second
pause. The gas control waits 2 minutes before turning on the blower for
another 30 seconds to see the circuit close. This cycle repeats as long as
there is a call for heat or until the circuit closes.

c.

Pressure switch or blower temperature switch opens during burner
operation-the gas control turns off the pilot and main valve, runs blower for

15 seconds (inter-purge) waiting for pressure switch and/or blower
temperature switch to close. If either switch fails to close, the control
proceeds as described in 3b above, if the circuit closes again by the end of
the inter-purge, the recycle counter is incremented, if the recycle count has
not reached its limit (4), another trial for ignition begins. If the recycle count
has been reached, the gas control turns off the blower and flashes 6 times
then, 2 times with 3 second pause. The gas control waits 5 minutes before
repeating ignition sequence.

4. Trial for Ignition Fault:
a.

Pressure switch opens during trial-the gas control turns off igniter and
pilot valve. The gas control proceeds as described in 3b above. If the
pressure switch closes within 30 seconds the gas control will continue with
trial for ignition starting at blower pre-purge.

b.

Flame not sensed-the gas control energizes the spark igniter attempting to
light the pilot and prove flame. If flame is not sensed within 90 seconds, the
igniter turns off, the pilot valve is closed and the gas control runs the blower

12

12

UPV Series

through post purge and flashes 6 times then, once with 3 second pause.
The control waits 5 minutes before repeating the ignition sequence.

Abnormal Operation (cont.)

5. Flame sensing fault:
a.

Flame lost during run-the gas control turns off pilot and main valves, runs
blower for 15 seconds (inter-purge). The gas control increments the recycle
count, if the recycle count has not reached its limit (4), another trial for
ignition begins. If the recycle count has been reached, the gas control turns
off the blower and flashes 6 times then, 3 times with 3 second pause. The
gas control waits 5 minutes before repeating the ignition sequence.

b.

Flame sensed out of sequence-the gas control only looks for pilot flame
when the blower is running. If flame is present when the pilot valve is not
open, the gas control proceeds to wait for flame loss and flashes 5 times with
3 second pause. This continues until flame is lost. Once the flame signal is
lost, the control flashes 6 times then, 4 times with 3 second pause.
control waits 5 minutes before repeating the ignition sequence.

The

13

13

UPV Series

Observe green LED indicator on
electronic gas control. Status flash
codes are displayed with a three second
pause before repeating. Check and
repair the system as noted in the
troubleshooting table below.

LED Status Control Status Probable Cause

None, control
LED not on or
flashing

Short flash, once
every four
seconds

“Heartbeat”
alternates
bright/dim

Short flash once
per second

Two flash, three
second pause

Three flash,
three second
pause

Four flash, three
second pause

Five flash, three
second pause

No electrical
power

Stand-by mode,
waiting for call for
heat (no fault).
Thermostat

calling
for heat (no fault).

Weak pilot signal
on last call for
heat.

Pressure switch
not working­closed position.

Pressure switch
or blower temp.
switch not
working -open
position.

Excessive tank
temperature.
System must be

reset.
Undesired-false
pilot flame
present.

Control power switch in “OFF” position.
Supply voltage interrupted.

Temperature demand is satisfied.

Tank temperature below set point of
thermostat.

1. Unstable pilot.

2. Pilot tube block or restricted.

3. Oxidation build up on pilot electrode.

4. Wire damage to pilot assembly or bad
connection at gas valve.

1. Pressure switch tubing kinked or blocked.

2. Blocked pressure tap on switch or blower.

3. Faulty pressure switch.

1. Vent blockage or improper vent

configuration.

2. Pressure switch tubing kinked or blocked.

3. Faulty pressure switch.

4. Blower not spinning up to speed.

5. Blower temp or exhaust temp too high.

6. Faulty blower temperature switch.

1. Temperature sensor out of calibration.

2. Faulty gas control.

3. Plumbing leak.

1. Pilot valve stuck in open position.

Service

Procedure

Turn power on.

Normal operation.
Adjust thermostat to
temp level.
Normal operation.
Adjust thermostat to
temp level.

Page 18.

Page 20.

1. Check vent or vent
tables.

2 & 3 Page 19.

4. Page 21.

5 & 6 Page 24.

1 & 2. Replace gas
control, page 27.

Replace gas control,
page 27.

14

14